


The Education of Alexander Lightwood: Fantasies

by AtowncalledMalec



Series: The Education of Alexander Lightwood [14]
Category: Shadowhunters (TV), The Shadowhunter Chronicles - All Media Types, malec - Fandom
Genre: (for lack of a better term) Cock Train, Anal Fingering, Canon with a twist, Dirty Talk, Double Alec, Double-Ended Dildo, Everyone Is A Bottom., Everyone Is A Top, M/M, Magnus Oop's A Lot, Masturbation, Mirror Sex, Multiple Orgasms, Threesome, blowjob, butt plug, cum sharing, handjob, slight choking kink, they're all thirsty, thirsty magnus
Language: English
Status: Completed
Published: 2019-12-19
Updated: 2019-12-19
Packaged: 2021-02-25 23:34:32
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 8,118
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21863821
Author URL: https://archiveofourown.org/users/AtowncalledMalec/pseuds/AtowncalledMalec
Summary: A couple of weeks previous, Magnus had split himself in two so that he and his doppelganger, Mags, could take Alec apart. Now it's his turn to experience what it's like to have two Alecs fuck him senseless.This work is not to be reposted anywhere else or translated without my permission.
Relationships: Magnus Bane/Alec Lightwood
Series: The Education of Alexander Lightwood [14]
Series URL: https://archiveofourown.org/series/1265225
Comments: 32
Kudos: 180





	The Education of Alexander Lightwood: Fantasies

**Author's Note:**

> The reason I'm posting this twice is that it was requested in the Third Smut Challenge. But of course, I had to post it here too.

Magnus crossed one leg over the other, as naked as the day he was born, fiddling nervously with the spine of the file in his hand. Looking up at his equally naked boyfriend, he couldn’t help but chew his lip at the thought of Alec’s request. He was half worried, half hard. More than half hard. But still worried.

"Are you sure you want to do this, Alexander? You know the risks if I can’t splice the two of you back together," Magnus asked, putting his own desires aside to be sure that Alec knew what he was asking for.

"Magnus, I trust you. Implicitly. I'm ready," Alec replied without a moment’s hesitation, reaching out to cup Magnus’ face. Not only did he trust Magnus, but he also wanted to show Magnus the same kind of pleasure that Magnus had shown him only a few weeks before, during their last lesson. 

They were back in the ‘classroom’. Magnus had worked his magic and restored their bedroom to the old classroom that he and Alec had used when he had taught Alec about sex. The same red walls. Same cabinets and bed, chains and breeding bench. He had even restored the table and chairs behind the door. Which they were currently sitting on.

"Come on, don't you wanna know what he's like?" Alec asked, smirking when he saw Magnus' glamour flicker. The tantalizing glimpse of gold and the elongation of Magnus' pupils told him all he needed to know.

Magnus did want to know what Alec's alter ego was like, wondering if - when he casts the spell- he’d get coy Alec, or confident Alec, or soft, loving Alec. When he’d split himself in half during their last lesson, his mischievous self had come out to play.

Only one way to find out.

Magnus stood, his boyfriend following, and centered himself. He drew on the centuries of knowledge and skill he's amassed. Reaching deep, he gathered his magic to cast the spell that would split Alec in two. Two different personalities, two bodies that would be able to take him apart, two sides of the same man. The man he loved.

Alec knew it was going to work, the moment Magnus' magic turned green. He looked down when the magic wrapped around him, sending a shudder down his spine.

Magnus watched carefully when Alec split into two people before his eyes, careful to be sure each half of his boyfriend was complete. His eyes flicked between the two, taking in the newcomer from head to toe. The doppelganger was an exact replica of Alec, down to the last hair on his chest. The only difference Magnus could see was that the newcomer had a side part, his hair slicked back. 

And then the second Alec opened his mouth. "I don't think we've been formally introduced. I'm Alejandro."

“What the fuck? I've never called myself Alejandro in my life!" Alec sputtered, staring at himself. At his doppelganger. At the man who just emerged from his body and left him feeling like half of himself was missing.

Magnus couldn't help but stare at the two Alecs, gawping at the newcomer until Alec 2 cracked up.

"I'm joking! Lighten up. Call me Alexander, Magnus. You can call him Alec," Alexander said, jerking a thumb over his shoulder at his other half as he stalked forward to take Magnus' hand. 

The fact that everyone was already naked only made the whole situation better, in Alexander's opinion. They could get straight to the fucking.

Alec felt an irrational flare of jealousy for a moment when his confident other half kissed Magnus' hand. Half because the doppelganger seemed to be naturally confident and flirty. Half because Alexander was kissing Magnus. Alexander was a part of himself and yet it still made him want to club the guy around the head.

Magnus couldn't help but be charmed by Alexander, his stomach tightening slightly from the gesture. He didn’t miss the rise of Alec's eyebrow.

"I can put you back together any time you want, Alec," Magnus said, wondering if Alec was regretting his decision.

"Uh-uh, he stays," Alec said. His doppelganger was the carefree part of himself that he always wanted to let out. He rarely got to be that person with anyone other than Magnus, his job demanding perfection all too often. It seemed to him that Alexander was just as shameless as Magnus' doppelganger, Mags, had been the first time they had tried this - when Alexander circled Magnus.

Magnus searched Alec's eyes when Alec stepped forward, his stomach clenching when he saw the challenge, mixed in with the lust that blew Alec's pupils wide.

Alec raised an eyebrow at his other half, watching Alexander stop behind Magnus, before pulling Magnus into a bruising kiss. He didn't know what surprised him more when Alexander stepped forward and pressed up against Magnus' back. The fact that the jealousy didn't flare up again, or the fact that the sight of Alexander, pressing a kiss to the side of Magnus’ neck, had his dick twitching.

Magnus didn't know where to look when Alec's lips trailed across his jaw and down the other side of his neck. His eyelids fluttered when a set of plump lips sucked a hickey onto each side of his neck. Now he understood why Alec had liked two Magnus' so much. With one firm cock pressed into the cleft of his ass and one rubbing against his own solid dick, he barely knew what to do with himself. But he liked it. A lot. 

"Let’s do the thing he likes," Alexander suggested when he pulled back, smirking when the confused expression on Alec's face morphed into a grin. Spinning Magnus on the spot, a grin that matched Alec’s spread over his face when Alec nodded at him. 

Alexander didn't hesitate to drop to his knees, long fingers trailing down the inside of Magnus' thighs to push Magnus' knees apart. “Open your legs for me, baby,” he said, encouraging Magnus to spread his legs with a teasing scrape of his nails. Looking up, he winked at Magnus before pressing a soft kiss to the leaking tip of Magnus' dick, tasting Magnus on his lips.

Alec’s eyebrows shot up when Alexander called Magnus “baby”. He wasn’t one for nicknames and often rolled his eyes if Magnus tried to find one he liked. It seemed his other half had other ideas though.

Magnus already knew what was coming. He certainly didn't complain when Alec’s hands slid around his stomach, Alec now molded to his back, and spread his legs wider for Alexander. A breathless moan escaped when Alec took hold of his dick and guided it into Alexander’s mouth. The two of them, confidently working together, turned his breathing shallow. He could barely breathe from the anticipation.

Alexander looked up at Magnus and raised one eyebrow in a silent question, half smirking around Magnus' dick when two of his fingers were suddenly lubed up with a snap of Magnus'fingers. He sucked Magnus all the way down to the base, gagging himself as he pushed a hand through Magnus' legs and searched his asshole out.

Alec stopped sucking hickeys into Magnus' neck long enough to look down, his dick impossibly hard when he watched Alexander's fingers sink slowly into Magnus' hole. Wrapping his fingers around those of his counterpart, he guided Alexander’s fingers, helping his other half finger their boyfriend.

The soft husky moan that Magnus let out was like music to Alec's cock, his favorite sound. His hips bucked forward of their own accord, his dick pressing harder into Magnus' ass cheek, desperate for friction.

“Does it feel good, Magnus? Having his lips around your cock and his fingers in your ass?” Alec asked, watching his other half as he rubbed his dick against Magnus’ ass cheek. The friction was perfect.

“So good… so… so…” Magnus couldn’t formulate a sentence when Alexander concentrated on the head of his dick and Alec reached around him once more, to jerk the remainder of his length.

Magnus just about had the presence of mind to reach back and take Alec's dick into his freshly lubed hand. The fingers, slowly opening him up, and the way Alexander's tongue swirled around the head of his cock, every time Alexander hollowed his cheeks and pulled back, threatened to steal all of his concentration but he focused enough to start jerking Alec off.

Alexander took Magnus' dick in deeper and deeper with every suck, giving zero fucks about the fact that he could barely breathe. The shake of Magnus' thighs, every time he did this, was one of his favorite things in the world.  _ Who needs air when you could watch your boyfriend lose it like that?  _

Alexander curled his fingers every time he pulled them back, almost falling from Magnus' ass, but not quite. The husky moans that Magnus let out and Magnus' rim, relaxing further around his fingers every time he brushed them over Magnus' prostate had him pulling his fingers out of Magnus' ass.

"Fuck!" Magnus muttered, his hips surging forward when Alexander pulled his fingers out of his ass. The word almost came out as a whine for how empty he felt. He could barely breathe from the pleasure of Alexander's mouth around his dick and Alec's mouth trailing kisses down his spine but he wanted more. 

Magnus wanted to feel that pressure in his ass, the pleasure of Alexander's fingers sliding through his rim, the waves of pleasure that wracked his entire body whenever his prostate was massaged. Or did he want to feel Alec’s cock slide in there instead? He couldn’t decide. He wanted it all and he wanted it now.

Alec nudged Magnus' ankles further apart when Alexander took hold of his dick and guided it to Magnus' entrance.

"Lube yourself up," Alec whispered in Magnus' ear, the words breathless from the anticipation that coursed through him and the sensation of having Alexander’s hand on his cock. He was more than ready to fuck the man he loved most in the world. 

"Do it, slick yourself up so he can sink his thick cock into your tight hole. It will feel so much better when he stretches you wide," Alexander said, pulling back off of Magnus' dick when Magnus looked down at him. He started jerking Magnus with the hand that wasn't wrapped around Alec's dick, the shaft as familiar as his own. Technically, it  _ was _ his own dick.

Magnus snapped the fingers of his right hand, lubing himself up, and slid his left hand into Alexander's hair for something to hold onto. His breath stuttered out when Alec pushed slowly into him, opening him up further, and Alexander took his dick into that sinfully hot mouth once more.

“Your tight little hole feels so good around my cock,” Alec moaned, bottoming out, Magnus clenching around the base of his shaft. “What does he taste like, Alexander?” he asked, looking at his counterpart over Magnus’ shoulder. The question had his counterpart popping off Magnus’ dick with an obscene noise.

“He tastes so good. I can’t wait to have him spilling down the back of my throat. I want to swallow every drop,” Alexander said, snaking the tip of his tongue up the underside of Magnus’ cock with a grin. Or maybe he didn’t want to swallow every drop. Maybe Alec would like the honor.

Magnus wanted to move desperately, to fuck into Alexander's mouth, to fuck himself on Alec's dick. He wanted to have it all. He thought back to his notes when they had been roleplaying teacher/student. Alec had always excelled at dirty-talk but two of them speaking like that was almost enough for him to blow his load.

Alec started moving as soon as Magnus' hips jerked. He gripped Magnus' hips hard and started out with shallow movements, barely able to hold himself back when Magnus clenched down, to let Magnus get used to his dick.

Alexander popped off of Magnus' dick to watch, continuing to jerk his boyfriend as he watched the other half of himself start to fuck Magnus harder. Unable and unwilling to stop himself, he took his own sadly neglected dick in hand, smirking when Magnus' eyes flicked down to his hand. 

Magnus always did love to watch Alec masturbate. It was no different with Alexander. There was something so hot about watching his boyfriend bring himself to release. 

Magnus would watch Alec as often as he could, learning all of the minute movements that would turn Alec into a quivering mess and apply them himself. The fact that he had a hand around his own dick and a dick in his ass only made the show hotter.

Alec picked up the pace when Magnus' movements became more insistent, the roll of Magnus' hips urging him on. He let loose the control he was holding over himself, slamming into Magnus' ass, again and again.

Magnus' fingers tightened in the thick waves of Alexander's hair when Alexander's tongue licked at the head of his dick, the minimal amount of air that he was able to inhale diminishing quickly as he pushed into Alexander's mouth.

Alexander only jerked himself harder, unable to help the gravelly moan that escaped around Magnus’ cock. The sound mingled with Magnus' husky whines, the ones that usually escaped when Magnus was about to come, and the shallow, desperate breaths that hissed from between Alec's teeth. He held his head still as he tugged at the head of his own dick, letting Magnus fuck into his mouth.

Magnus came with a low grunt, his hips jerking spasmodically from the overload of stimulation. It was all too much, the breath on the back of his neck, the deep moans that Alexander let out, the angle that Alec fucked him at. He shot his load all over Alexander's chin and into his waiting mouth when Alexander pulled back. His lungs quit when he saw the pearly drops all over Alexander's face.

“Look at his face, covered in cum. You want to kiss him, don’t you? lick it off?” Alec asked, pressed himself further into Magnus' body, pushing deeper when Magnus came. He had always had a thing about his cum coating Magnus’ face. To see Magnus’ pearly drops all over a mirror image of his own face was breathtaking. 

“Kiss him, Magnus. I want to watch,” Alec moaned, thrusting into Magnus again. It would be like watching in a mirror. Except he’d get to see it from a different angle. His own orgasm wouldn't be far behind, not with the way Magnus' back arched so beautifully.

Magnus bent at the waist, a few stray drops exploding from the head of his cock, and caught Alexander's lips in a searing kiss, uncaring of the mess on Alexander's chin. Every thrust into his ass threatened to get him hard again so he focused on invading Alexander's mouth to ground himself with the familiar kiss. 

Magnus’ eyes widened when he realized Alexander hadn’t swallowed his cum as he’d first thought. Not only did he taste himself on Alexander’s tongue, but Alexander also pushed his cum into his mouth. Straightening up. He looked over his shoulder at Alec, eyes wide, with a mouthful of his own cum.

“What did you do?” Alec asked his counterpart breathlessly, pausing his thrusts when he saw the expression on Magnus’ face. It was part shock, part lust, part raw desire.

“Gave him a taste of is own medicine,” Alexander grinned. When Alec raised an eyebrow in question, he elaborated. “I pushed his cum into his mouth. I thought you might want to swallow it,” he shrugged, winking at his counterpart.

Alec met Magnus’ gaze before hooking a finger under Magnus’ chin, drawing their lips together. Flicking his tongue over Magnus’ bottom lip, he swept it inside when Magnus opened up, taking the cum into his own mouth.

“You taste so good,” Alec whispered against Magnus’ lips when he swallowed Magnus’ load down. Magnus’ expression had his hips snapping forward once more.

“Fuck,” Magnus muttered, staring at his boyfriend over his shoulder. His eyes flicked down to Alexander, shaking his head when Alexander just winked. He knew Alec had a thing for cum but...

Alec’s eyes flicked down, over Magnus’ shoulder, to see that Magnus was impossibly hard again. The sight of Magnus’ bobbing dick was enough to push him over the edge. He came with a hoarse grunt, slamming his hips forward with one final thrust to grind into Magnus' ass. His balls were practically lodged in his stomach but he couldn't give a shit, he was too busy filling Magnus' ass up. 

Alexander followed Alec, his own hips jerking as he spilled into his hand. His grip had already been perfect but seeing how hot Magnus found them was enough to have his balls drawing up. Their warlock never judged them, only ever encouraging them to explore. 

Magnus probably would have collapsed if Alec hadn't held him up. His boyfriend Was practically glued to his back anyway but Alec's grip tightened when his knees threatened to go from underneath him. A groan escaped him when Alec pulled out of his ass slowly. 

“Hold it in, Magnus. Clench down,” Alec said breathlessly, sliding his thumb into Magnus’ fucked out hole to keep his cum in there when his cock slipped out of Magnus’ ass. When it was in place, only a small amount of cum seeping around his thumb, he caught Alexander’s attention and flicked his head in the direction of the cabinets. 

Alexander winced second hand for Magnus when Alec pulled out of Magnus' ass. He knew that empty feeling well, disliking it as much as Magnus did. As shakey as his legs were from his own orgasm, he took the hint from Alec. Standing, he crossed the room to the cabinets, pulling a buttplug out of the one designated for that purpose and returned to his other half’s side.

Alec took the plug from Alexander and slid it into Magnus’ ass, eyes glued to Magnus’ rim when it stretched around the toy.

When Magnus was full again, groaning under Alec’s touch, Alexander tugged Magnus and Alec over to the bed, needing a minute to recover properly. Pressing himself against Magnus’ back when they all lay down, he let his fingers curl over Magnus’ hip, occasionally straying over Alec’s hip too.

Alec curled into Magnus’ chest, sandwiching Magnus between him and Alexander. He needed a moment to get his breath back. The fingers that curled over his hip when he pressed himself flush to Magnus, their legs entwined, felt nice. 

Alec was surprised when he looked down and realized they were Alexander’s fingers. He didn’t know why the pleasure of the touch surprised him so much, he was basically touching himself. Magnus was the only person who knew his body as well as Alexander did.

“I feel like I’ve created a monster,” Magnus said, shuddering from the friction against his prostate when Alec and Alexander simultaneously pressed close to him, Alec pressing him back and peppering his lips with kisses, Alexander’s cock pressed against his plug, ghosting kisses over the nape of his neck.

“If you aren’t having fun…” Alexander said, looking over Magnus’ shoulder. A grin quirked the corners of his lips up when Magnus pulled back from Alec’s kisses to aim an incredulous expression his way. “Good, because this is your chance to see us do all the things you ever fantasized about,” he said, rocking his hips forward.

Alec laughed when Magnus’ face lit up, his boyfriend’s thoughts practically rolling across his face. “Anything,” he whispered an inch from Magnus’ lips, his fingers trailing over Magnus’ stomach to his cock, lightly caressing the hard shaft that pressed against his own.

“I think he has something in mind,” Alec said, meeting Alexander’s gaze when Magnus’ eyes flicked to the cabinets.

“Anything?” Magnus asked, his eyes flicking from Alec to Alexander. When they both looked at him and nodded, he bit into his lower lip, wondering if they truly meant it. Untangling himself from the pile of limbs and cocks they had become, he crawled off the bed and crossed the room, aiming for the dildo cabinet. 

Alexander sat up when Alec did, both of them bringing their knees up and wrapping their arms around them to watch what Magnus was doing. Intrigue shot through him when Magnus dug out a bottle of lube from the lube drawer before pulling the dildo cabinet open.

Alec met Alexander’s gaze when Magnus turned to show them what he had plucked from the cabinet. Magnus almost looked as if he expected one or both of them to bolt. Judging by the equally intrigued expression on Alexander’s face, he knew there was no way in Edom that was happening. 

“Which one of us?” Alexander asked, eyeing both ends of the double-ended dildo Magnus held up. He kind of hoped Magnus would ask him to share it with him, rather than Alec. He didn’t get out enough and was having the time of his life.

“Actually… I was wondering if you would share it with each other,” Magnus said, keeping his fingers crossed that they would agree. As appealing as the idea of him and either half of his boyfriend sharing the dildo was, he couldn’t help but want to tug his cock to the mental image of them fucking themselves on the thick fake dick.

“We did say anything,” Alec said, meeting Alexander’s gaze once more. When Alexander shrugged and made space between them for Magnus, he turned back to their boyfriend and beckoned Magnus with a curl of his finger, patting the bed between him and Alexander.

Magnus didn’t hesitate, launching himself at the bed, his stomach fluttering with anticipation. Wedging himself between them, he dragged Alec and Alexander’s faces closer, kissing both of them breathless in turn.

“It’s your show. How do you want us?” Alexander asked when Magnus let him up for air. 

Magnus chewed his lip, gaze flicking between Alec and Alexander. “On your hands and knees, facing the foot of the bed, both of you,” he said after a moment, grinning when they complied.

Alec arched his back, looking over his shoulder when he was in position. The sight of Magnus shuffling onto his knees behind him and Alexander had anticipation curling through his stomach. This might be the oddest situation he had ever been in, and he had once taken a potion that had kept him cumming for hours. 

Magnus dropped the dildo on the bed and flicked the cap of the lube bottle open. He poured a large amount down the clefts of Alec and Alexander’s asses, ensuring he used plenty. When the lube was dripping onto the bed, he dropped the bottle too and skimmed both hands up and down their cracks. Good job he was ambidextrous.

Alexander’s groan matched that of his counterpart when Magnus’ finger slid into his ass. The pressure was amazing enough for him to push back, wincing slightly when the eager move had a pain ricochet through his rim.  _ Calm down, you thirsty hoe _ , he silently muttered at himself, trying to control himself more. Letting Magnus do the work, he held still while his warlock opened him up properly.

Alec had no compunctions about rocking on Magnus’ fingers, enjoying the slight sting when he was too eager. A deep, husky yelp escaped when a vibration pulsed through his prostate. Magnus’ magic. And he wasn’t the only one who got a dose of it, a matching yelp being barked out by Alexander.

Magnus teased a second finger into each hole when his magic had his boyfriend opening up. Both halves of him. He set up a steady rhythm of twisting thrusts in each hole, simultaneously, fingering them both open with the thrusts and the pulses of magic. It didn’t take long to feel both rims relax around his fingers.

“These assholes are perfect,” Magnus muttered, watching Alec and Alexander squirm on his fingers, each of them clearly trying to take more of his fingers in. When he judged that they were both ready, he pulled both hands back, grinning when both Alec and Alexander, whined for more. 

“You’d better fill them with something then,” Alexander said over his shoulder, clenching down on thin air. He should be clenching down on a cock. At least.

Alec agreed with his doppelganger. He wanted something thick in his hole, to fill him up, feeling horribly empty. When Magnus tugged at his hip, he straightened up, watching Magnus over his shoulder.

Magnus maneuvered Alec and Alexander into position without a word, thanking the angel that neither of them seemed to have no problem with his request. Then again, Alec had surprised him every step of the way during their sexual adventures. When Alec and Alexander knelt on the mattress, back to back, he lubed the dildo up generously.

Alexander watched Magnus’ movements, eyeing the dildo. It had to be a total of fourteen inches in length. The rubber was flesh-colored, a perfect match to the pigment of Magnus’ cock, quite bendy and at least an inch to an inch and a half in diameter. When it was dripping with lube, he practically snatched it from Magnus and started feeding one end into his ass, stretching himself wide with it. 

Alec looked over his shoulder when he heard Alexander’s deep, gravelly moan. Seeing Alexander stuffing the dildo into his ass like someone was going to steal it from him, he rolled his eyes. His other half was a grade-A hoe. When his eyes flicked to Magnus, however, a grin spread over his face. Magnus couldn’t take his eyes off Alexander’s rim.

“Leave some for me. You’re such a slut for cock,” Alec said, reaching behind him to take the other end of the dildo. The expression on Magnus’ face, when Magnus ripped his eyes away to meet his gaze, had him pressing the wide head of the dildo to his rim, moaning when he breached himself.

Magnus’ brain almost short-circuited. Never in his wildest dreams, when he and Alec had sat on his couch and talked about Alec’s education all those months ago, had he dreamed that he would be in a situation like this. Or that Alec would become the confidant man he saw before him. Times two. Alexander might be the more confident, slightly more dominant part of Alec but he loved every part of his boyfriend equally.

Alec pushed back on the dildo when Magnus seemed to come to his senses and took hold of it in the middle. He felt like he was stretched impossibly wide but it was a good stretch, the nerves in his rim lit up like Christmas. When his rim pressed against Magnus’ hand, he stopped, getting used to the feeling of being full. He had been stretched wider than this. Hell, he had taken Magnus’ and Mags’ dicks at the same time. 

Alexander’s fingers curled into the sheets when the dildo was fully sheathed inside him, relaxing around the dildo in increments. It felt good in his ass, especially when Magnus’ pinky finger flicked over his rim, sending a shudder of pleasure through him. 

“I want you both to fuck yourselves on this and cum untouched,” Magnus said, looking from Alec to Alexander when they both glanced over their shoulders at him. Seeing the grin on Alexander’s face, and the smirk that tugged the corners of Alec’s face up, he snapped his fingers twice in quick succession before letting go of the dildo.

Magnus’ cock twitched when two loud, mewling whimpers decimated the momentary silence of the room. He had used his magic to fix the dildo in place, in mid-air, so that no matter how hard either half of his boyfriend fucked themselves on the fake dick, it wouldn’t move. He had also set a pulse of his magic into the rubber so that it would vibrate, as hard as a vibrator would.

“Fuck!” Alec groaned, his hips jerking automatically when he felt Magnus’ magic pulse through his ass. The vibrations were strong, making him buck on the dildo. Straightening up to relieve some of the pressure on his prostate, he found that the position did little to alleviate it. Not that he was complaining. It felt amazing. Gripping his thighs, he rocked his hips, another desperate whimper escaping when the dildo scraped over his nerves.

Alexander lost the strength in his arms from the strength of the vibrations. Burying his face in the crook of his elbow when he landed face down in the mattress, he fucked himself on the dildo, unable to stop the grunts that escaped him. It felt too good. The harder the vibrations pulsed through him, the faster he moved, back arched, knees splayed wide, rim stretched unbelievably wide. Feeling Alec’s ass slam back against his own only made him moan louder.

Magnus had to take his dick in hand, tugging himself furiously. How could he not when he saw the identical stretch of Alec and Alexander’s assholes around the dildo? Their rims clung to the rubber cock, the most gorgeous whimpers escaping both Alecs whenever the vibrations shot through their nerves. He used a tricky spell to link the vibrations to his own pleasure. The harder he tugged his dick, the more powerful the vibrations became.

Alec wanted to grab his dick, badly. Rolling his hips, he couldn’t stop his hands from skimming up and down his thighs, inching closer to his cock each time. The vibrations that pulsed through his nerves were strong, rumbling through his body in every direction. 

A husky moan from Alec’s left had him turning his head to see Magnus jerking his dick furiously. Knowing that Magnus was getting off, he rocked harder on the dildo, feeling every inch that he slammed his ass back on. Every time he thrust backward, his ass cheeks slammed against Alexander’s ass, sending a loud clap of skin meeting skin through the room.

“I’m so fucking full,” Alexander shuddered, barely able to get the words out in one coherent sentence. His aching lungs had his moans stuttering out of him. The sounds of Alec’s equally breathless, gravelly whimpers, and the soft, husky moans that escaped Magnus had him working harder, arching his back to slam backward on the thick dildo.

It was almost too much for Magnus, watching both halves of his boyfriend jerk on the fake dick. Their legs shook harder than his own did. Twisting his hand every time he tugged his dick, he ramped the vibrations up ridiculously high, his balls drawing up when Alec and Alexander let out twin grunts.

“Magnus! Fuuuk!” Alec cried, losing the strength from his body when the vibrations in his ass rocketed. He had to bury his face in the mattress, his hands curling into his hair to stop himself from taking his cock in hand. Out of options, he simply slammed his ass backward, slamming it into Alexander’s ass, on the verge of cumming.

“Fuck, fuck, fuck! I can’t... Magnus, it’s… fuck!” Alexander mewled, slamming his ass back, unable to stop himself. Losing his mind over the insane pleasure that consumed him, he simply started grinding on the dildo, raising his hips as he did to put constant pressure on his prostate. It took all of three seconds for him to cum, grunting into the mattress like a wild animal when his cock exploded all over the sheets.

The sound of Alexander’s orgasm was enough to push Alec over the edge too. How could he not with the overload of sensations that wracked his entire body? His balls slammed up, dragging an orgasm from him that was almost too powerful. With a keening whimper, he slammed his body forward and collapsed onto the mattress, shuddering, even if the dildo no longer filled his ass.

Magnus came almost as hard as Alec and Alexander, unable to drag his eyes away from Alexander. The doppelganger had already cum once but he kept on rocking on the dildo, taking more of it in now that there was no other ass there to counteract his thrusts. When his balls drew up, his slit painting the sheets white, he unintentionally ramped up the vibrations.

Alexander came again, gasping for breath, unable to make any sound other than a high pitched whine. His balls contracted so hard that a small section of his brain worried for them. Collapsing forward, his grunts coming out in a broken staccato, he face-planted the mattress and refused to move. Even now, after pulling off the dildo, his balls spasmed uncontrollably.

Cleaning the dildo and replacing it in its cabinet with a wave of his hand, Magnus flopped back onto his ass, gasping for breath. He stared at the two halves of his boyfriend, eyes flicking from one to the other, half in awe, half in shock. Grabbing their wrists, he tugged at them both until they shuffled closer and wrapped themselves around him, the three of them fighting for air.

“That was amazing,” Alec muttered into Magnus’ chest, eyes slammed closed against the tiny aftershocks that rumbled through his balls. Unable to open his eyes, he didn’t know who’s legs were curling around who’s and didn’t really care.

Alexander just nodded into Magnus’ chest, too fucked out to form words. Almost of their own volition, his fingers moved in rune patterns when he felt someone’s cum under his fingertips. He didn’t know who’s it was, only that it wasn’t his own. That was splattered all over his thighs.

“Anyone want a drink?” Magnus asked, his throat parched. When two heads nodded into his chest, one on either side of him, he forced himself to sit up against the pillows and headboard. Snapping his fingers, he conjured three martinis and sipped his, smiling when Alec and Alexander sat up a little and curled into his sides to sip theirs.

“I need my stele,” Alexander mumbled, finally able to get more than a grunt passed his lips. Holding his hand out, a smile split his face when Magnus conjured his stele. Swiping it over his stamina, strength, endurance, and flexibility runes, he relaxed a little when the energy from them infused his body.

Alec took his stele from Alexander and swiped it over his own runes, choosing the same ones as Alexander. When he was done, he dropped his stele on the nightstand and curled into Magnus once more.

“It’s alright for some,” Magnus muttered, eyes flicking from Alec to Alexander. He had no stele to magically bring him back to life. Then he remembered that he actually had magic. Draining his glass, he filled it with a restorative potion with a wave of his hand and sank it in three gulps. The potion took effect almost immediately.

When Alec felt Magnus’ cock stir to life against his thigh, his fingers wandered down Magnus stomach to skim over his boyfriend’s length. It hardened under his touch, a smirk flitting over his face when he met Alexander’s gaze, his doppelganger’s face a couple of inches away from his own.

_ Might as well make the most of it _ , Alexander thought, cupping Magnus’ balls, massaging his sac. Letting one finger snake down, he started rubbing at Magnus’ taint, applying a little bit of pressure to Magnus’ P-spot. It was Magnus who had taught them about that spot after all.

Magnus stared down at Alec and Alexander’s hands, spacing out a little form the pleasure that flooded him. They were insatiable. He couldn’t even find it in him to complain. It felt too good. With a thought, he sent their empty glasses away, slumping a little further down the bed.

Alec stroked Magnus until his boyfriend was fully hard. When Magnus’ solid length started pushing into his hand, he let go for a moment to roll over, his back to Magnus’ side. Reaching back, he tugged at Magnus’ wrist until Magnus rolled over too, plastered to his back. Taking Magnus’ dick in hand, he brushed it up and down his crack, pushing back when the head of Magnus’ cock slipped into his still-loose hole.

Magnus let out a husky moan when he filled Alec’s ass. The small amount of time that had passed since Alec had fucked himself senseless on the dildo meant that Alec had tightened up a little, making Alec’s rim squeeze around his cock. “You feel so good,” he said, breathlessly, curling into Alec’s back.

Alexander slid his hand down the back of Magnus’ thigh. When he reached the back of Magnus’ knee, he lifted Magnus’ leg and draped it over Alec’s hip, exposing Magnus’ filled hole perfectly. 

Watching Magnus fuck into Alec, Alexander almost forgot what he wanted to do. The way Magnus was wrapped around Alec, curled over his counterpart’s body, rutting into Alec’s ass was breathtakingly beautiful. He watched for a while but the sight of Magnus fucking his mirror image soon became too much.

“Can anyone join this party?” Alexander asked, peeking over Magnus’ shoulder. He had his answer when Alec stopped moving against Magnus and turned to look at him.

Alec patted Magnus’ hip before pulling off of his boyfriend’s dick. He rolled up onto his knees, meeting Magnus’ gaze over his shoulder and tugged at Magnus’ hand until Magnus knelt behind him. Reaching between his and Magnus’ bodies, he lined Magnus’ dick up with his hole once more and thrust back on it.

“If our boyfriend has no objections, why don’t you pull that plug out of his ass and fill it with your cock?” Alec asked over his shoulder, rolling his hips. Unable to stop it, a moan escaped him when Magnus moved at the same time, the roll of Magnus’ hips meeting his own.

“Please,” Magnus groaned, tilting his head when Alexander climbed to his knees behind him and Alexander’s lips saught his neck. Wanting to feel every inch of Alec, his hand wandered over Alec’s hip, aiming straight for Alec’s cock. Wrapping his fingers around Alec’s solid length, he started jerking his boyfriend with lazy strokes.

Alexander’s own cock ached so he took the base of the buttplug between his fore-finger and thumb and tugged it gently from Magnus’ hole. Before too much of Alec’s cum from earlier could drip out, he gripped the base of his cock and pressed the head of it to Magnus’ creamy, dripping hole, filling his boyfriend with one smooth thrust that buried him to the hilt on Magnus’ next backward thrust.

“Fuck!” Magnus breathed, reaching back with his free hand to pull Alexander’s head closer. Turning his head, he met Alexander’s lips in a bruising, desperate kiss, breathing hard from how full he was and how good it felt to buried in Alec’s tight channel.

When Magnus broke the kiss, Alexander rolled his hips back until he almost fell from Magnus’ ass before thrusting deep into Magnus’ body, watching Magnus tug Alec’s head around to claim his lips too. 

Alec caught Magnus’ moan, meeting it with one of his own. His doppelganger had fucked Magnus so hard that Magnus’ hips had inevitably bucked forward, filling his ass once more. His shallow breaths mingled with Magnus as he rocked back on his boyfriend’s dick. The tight grip Magnus had on his dick had him chasing Magnus’ hand.

Alexander gripped Magnus’ hips, helping his warlock move. Shuffling as close as he could, he molded himself to Magnus’ clammy back, savoring the feeling of their skin gliding against one another. All of them had broken out in a sweat, each of them moving desperately against the other. Watching Magnus and Alec over Magnus’ shoulder had him fucking into Magnus’ ass harder. 

Magnus took control of their movements when Alexander’s hand wrapped around his own, helping him jerk Alec a little faster. He leaned back into Alexander’s body when Alexander’s lips trailed down his neck and over his shoulder, arching his back to thrust deeper into Alec’s ass.

Magnus could barely breathe from the pleasure of being sandwiched between both halves of his boyfriend but being filled with Alexander’s cock and having his own cock sheathed in Alec had his hips rolling in a rhythm that was as steady as he could make it, fucking Alec with deeper thrusts, fucking back on Alexanders cock. Which wasn’t very steady at all.

“Wait a minute, hold still, both of you. I want to try something,” Magnus said when their movements became too sloppy and rushed. When Alec and Alexander complied, he released Alec’s dick and gripped both of Alec’s hips instead. He started rolling his hips in a smooth rhythm that had all of them moaning, using Alec’s hips and his natural dance ability to his advantage. 

Alec reached down and started jerking himself off, wondering if Magnus’ fingertips would leave marks on his hips from the tight grip his boyfriend had. He found that he didn’t give a fuck, liking the idea. With his free hand, he tugged at his right nipple, unable to stop himself. It all felt too good but he still wanted more.

“Fuck yourself on my cock,” Magnus whispered in Alec’s ear, seeing what Alec was doing over Alec's shoulder. He wanted to see properly so he snapped his fingers and conjured a mirror, setting it beside the bed so they could all watch themselves. They looked unbelievably hot. 

When Alec's movements synced with his, Magnus looked at Alexander over his shoulder, meeting his beautiful hazel gaze. "Fuck me, Alexander. Fuck me hard," he said. 

Alexander didn't need telling twice. He moved in time with Alec and Magnus, their thrusts now smoother, all three of them working together. Gripping Magnus' hip with his left hand to keep himself steady, he wrapped his right hand around Magnus' throat, plastering himself to Magnus' back so he could trail kisses along Magnus' jaw. 

Magnus couldn't help the husky moan that escaped him when Alexander's long fingers wrapped around his throat it wasn't hard enough to hurt or restrict his breathing, too much. The way Alexander rutted into his ass and Alec clenched on his cock did that. 

"We look so fucking hot," Alexander whispered in Magnus, ear, pressing his cheek to Magnus' as his fingers tightened infinitesimally. Their reflection was the hottest thing he'd ever seen. "Look at him, taking his pleasure unashamedly. You did that for us," he said breathlessly, snapping his hips forward in another deep thrust. 

"I only showed you," Magnus breathed, meeting Alexander's gaze in the mirror for a moment. "You're the one that ran with it," he said, eyes flicking to watch Alec when Alexander did the same thing. They both watched, their panting breaths ragged from watching Alec. 

A small part of Alec's brain heard the conversation going on behind them but he was too lost to the pleasure of his own hands and Magnus' cock to pay any attention. He twisted each nipple in turn as he tugged the head of his cock with twisting, desperate pulls. 

Opening his eyes when he found the strength, Alec looked up, his balls tightening when he saw Alexander's hand around Magnus' throat, watching Alexander fuck into their warlock. It was too much. He came hard, spilling into his hand and down his thighs with a gravelly moan. 

"Fuck. So fucking tight," Magnus groaned when Alec clenched down on his dick. The tight rim of Alec's hole had his hips jerking forward to slam into Alec's ass, only making him clench down on Alexander's cock. Gripping Alec's hips harder, he pulled his Shadowhunter back against him to plaster Alec's back to his front. 

"Use my ass like a fuck hole," Alec muttered. Even after cumming, he was still too lost to the pleasure of having Magnus inside him to object. 

The words sent Magnus hurtling over the edge, his hips snapping forward so he could grind into Alec. With a husky moan, he spilled deep in Alec's ass, leaning back into Alexander's grip around his neck as he did. 

Alexander picked up the pace when Magnus started clenching on his dick. He wanted to get there before Magnus collapsed. Alec already looked like he was on the verge of doing so. A hand on his hip, sending a deep pulse of vibrating magic into his body got him there. Magnus always did know how to play his erogenous zones like a fiddle, hitting them all at once. 

Alexander lost his breath at how fast and hard he came, filling Magnus' fucked out hole with another load. Just thinking of his and Alec's cum swirling in Magnus' body had him burying his grunting moan in Magnus' shoulder. 

Alec reached back past Magnus and tugged at Alexander's arms until they were wrapped around the three of them, his counterpart's hands just reaching. Leaning back, he tilted his head with an exhausted grin when Magnus nuzzled into his neck. All three of them looked thoroughly fucked out in the reflection of the mirror. 

Magnus pressed a sucking kiss to Alec's neck, smiling when he saw how content Alec was in the mirror. He lived for that smile. The stretch on his rim, however, was becoming uncomfortable. Tapping Alec's hip, his eyelids fluttered when his cock fell from Alec's body, Alec pulling off it. 

Magnus did the same, pulling off Alexander's dick. He winced a little but consoled himself with the cum that dribbled out of his abused hole. A loud laugh burst from him when Alec shuffled around to watch, Alexander, doing the same. He pushed a little of the cum out of his ass for their obsessive viewing pleasure before his knees gave up on him. 

Shuffling until he was sitting on his ass, back pressed against the headboard, Magnus tugged at Alec's hand until Alec lay beside him, Alec's head resting in his lap. He laughed when Alexander collapsed in a heap, sprawling on top of the pair of them.

Alexander curled into Alec and Magnus, wrapping himself up in their bodies. His eyelids fluttered when Magnus' fingers curled into his hair and skimmed down his neck to pull him closer by his shoulder, a rumble of laughter making Magnus and Alec's bodies shake. He was exhausted but completely satiated 

"Well that was fun," Alexander muttered, laughing just as breathlessly as Alec and Magnus were. He curled further into Magnus' chest, legs draped over Alec's and fiddled with one of the rings on Magnus' finger. 

"Maybe next time you could invite Mags to join us and we could have a good old fashioned gang bang?" Alexander suggested, grinning when Alec choked. He didn't miss the way Alec and Magnus’ eyes lit up at the prospect. His other half was a thirsty hoe too.

Alec grinned at the thought, trailing his fingers over Magnus' legs as he imagined what Alexander and Mags could do with one another. It had his dick giving a little twitch against Alexander's leg. He rolled his eyes when his other half felt the movement and wiggled his eyebrows at him. His counterpart was ridiculous! 

"Okay, send me back. I need a nap," Alexander said before pulling Magnus into a deep kiss that made his blood sizzle. A small grin spread over his face when he pulled back and met Alec's gaze.

"Don't even think..." Alec was cut off when Alexander grabbed his face and smacked their lips together, memories of when Mags had done the same thing to Magnus surfacing.

Magnus burst into a fit of laughter when Alexander pulled back. The doppelganger was just like his own alter ego. He snapped his fingers when Alec aimed a playful kick at the counterpart, breathing a deep sigh of relief when the two Alecs melded back together again, safe and sound. 

"Did you have fun?" Alec tiredly asked Magnus when his boyfriend sank into him, Magnus curled around his body. It was nice to be whole again.

"It was amazing! Did you?" Magnus asks, letting his fingers curl through Alec's chest hair.

"I want to do it again. And I think Alexander was just happy to be let out," Alec said.

"He did have a point about Mags though," Magnus chuckled.

"Raziel, imagine the two of them meeting. They'd exhaust the pair of us!" Alec groaned.

"It would be fun to watch though," Magnus said, his grin widening when he felt the laughter rumble through Alec's chest. “Pizza?" he asked, snapping his fingers when Alec wholeheartedly agreed with his pizza plan.

_ Yeah _ , Alec thought as he tucked into his pepperoni pie - and whined at the pineapples on Magnus'-  _ it would be fun to watch. _

  
  
  


**Author's Note:**

> If anyone is reading this, please let me know if you think this chapter fits in with the others. I wrote these almost a year apart.


End file.
